Temporal contrast sensors (some examples of which are sometimes referred to as Dynamic Vision Sensors) are a class of sensor arrays whose sensing elements respond asynchronously to relative changes in incident intensity, i.e., changes in irradiance, also referred to as temporal contrast. The sensor output is an asynchronous stream of pixel address-events that directly encode temporal brightness changes in the scene that is imaged onto the array, thus reducing data redundancy while preserving precise timing information. Sensors of this sort are described, for example, by Lichsteiner et al., in “A 128×128 120 dB 15 μs Latency Asynchronous Temporal Contrast Vision Sensor,” IEEE Journal of Solid-State Circuits 43:2 (2008), pages 566-576.
Depth sensors enable the remote measurement of distance to each point on a target scene—so-called target scene depth—by illuminating the target scene with one or more optical beams and analyzing the reflected optical signal.